During the past 30 years, the number of patients with cancers that originate near the junction of the esophagus and stomach has increased approximately 600 percent in the United States. The first extensive probe of the DNA of these esophageal adenocarcinomas (EACs) has revealed that many share a distinctive mix-up of letters of the genetic code, and found more than 20 mutated genes that had not previously been linked to the disease.